// Collect `dst_root` constraints that are applicable to the values defined in
  // the `src_root` cluster.
  ValuesConstraintSet constraints = members[src_root].constraints;
  members[dst_root].constraints.Walk([&](Value v, ValueConstraint constraint) {
    Operation *op = v.getDefiningOp();
    if (op && filter(op)) constraints.Insert(v, constraint);
  });

        <constraint name="__context__" within="" contains="" />
        <constraint name="TYPE" within="" contains="" />
        <constraint name="ARR" nameOfExprType=".*\[\]" within="" contains="" />
        <constraint name="RES" nameOfExprType="boolean" exprTypeWithinHierarchy="true" within="" contains="" />
        <constraint name="ITEM" within="" contains="" />
        <constraint name="TARGET" within="" contains="" />

	// least one label must be prepended, but only for URI and email
	// constraints, not DNS constraints. The code also supports that
	// behaviour for DNS constraints.

	mustHaveSubdomains := false
	if constraint[0] == '.' {
		mustHaveSubdomains = true
		constraint = constraint[1:]
	}

	constraintLabels, ok := domainToReverseLabels(constraint)
	if !ok {

				if err != nil {
					return nil, nil, nil, nil, err
				}
				ips = append(ips, ipNet)

			case strings.HasPrefix(constraint, "email:"):
				emailAddrs = append(emailAddrs, constraint[6:])

			case strings.HasPrefix(constraint, "uri:"):
				uriDomains = append(uriDomains, constraint[4:])

			default:
				return nil, nil, nil, nil, fmt.Errorf("unknown constraint %q", constraint)

	sql = "CONSTRAINT ? FOREIGN KEY ? REFERENCES ??"
	if constraint.OnDelete != "" {
		sql += " ON DELETE " + constraint.OnDelete
	}

	if constraint.OnUpdate != "" {
		sql += " ON UPDATE " + constraint.OnUpdate
	}

	foreignKeys := make([]interface{}, 0, len(constraint.ForeignKeys))
	for _, field := range constraint.ForeignKeys {
		foreignKeys = append(foreignKeys, clause.Column{Name: field.DBName})

						if rel.Field.IgnoreMigration {
							continue
						}
						if constraint := rel.ParseConstraint(); constraint != nil &&
							constraint.Schema == stmt.Schema && !queryTx.Migrator().HasConstraint(value, constraint.Name) {
							if err := execTx.Migrator().CreateConstraint(value, constraint.Name); err != nil {
								return err
							}
						}
					}
				}

        call(self, dependencyOrDependencyConstraint, null);
    }

    /**
     * Add a dependency or dependency constraint.
     *
     * @param dependencyOrDependencyConstraint dependency or dependency constraint to add
     * @param configuration an action to configure the dependency or dependency constraint
     */

				}

				// If the constraint contains an @ then
				// it specifies an exact mailbox name.
				if strings.Contains(constraint, "@") {
					if _, ok := parseRFC2821Mailbox(constraint); !ok {
						return nil, nil, nil, nil, fmt.Errorf("x509: failed to parse rfc822Name constraint %q", constraint)
					}
				} else {
					// Otherwise it's a domain name.

			implicit = r.bool()
		}
		constraint := r.typ()
		if implicit {
			iface, _ := constraint.(*types.Interface)
			if iface == nil {
				errorf("non-interface constraint marked implicit")
			}
			iface.MarkImplicit()
		}
		// The constraint type may not be complete, if we
		// are in the middle of a type recursion involving type
		// constraints. So, we defer SetConstraint until we have

// is called through an exported API call such as AssignableTo. If constraint
// is set, T is a type constraint.
//
// If the provided cause is non-nil, it may be set to an error string
// explaining why V does not implement (or satisfy, for constraints) T.
func (check *Checker) implements(pos token.Pos, V, T Type, constraint bool, cause *string) bool {
	Vu := under(V)
	Tu := under(T)